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ogdoad

[og-doh-ad]
noun
  1. the number eight.
  2. a group of eight.

Origin of ogdoad

1615–25; < Late Latin ogdoad- (stem of ogdoas) < Greek ogdoás, derivative of ógdoos eighth; see -ad1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for ogdoad

ogdoad

noun
  1. a group of eight

Word Origin for ogdoad

C17: via Late Latin from Greek ogdoos eighth, from oktō eight
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012